<template>
  <div>
    <van-list
  v-model="loading"
  :finished="finished"
  finished-text="没有更多了"
  @load="onLoad"
>
    <!-- 评论列表 -->
    <div class="cmt-list" :class="{'art-cmt-container-1':isShow,'art-cmt-container-2': !isShow}">
      <!-- 评论的 Item 项 -->
      <div class="cmt-item" v-for="obj in commentList" :key="obj.comm_id">
        <!-- 头部区域 -->
        <div class="cmt-header">
          <!-- 头部左侧 -->
          <div class="cmt-header-left">
            <img :src="obj.aut_photo" alt="" class="avatar">
            <span class="uname">{{obj.aut_name}}</span>
          </div>
          <!-- 头部右侧 -->
          <div class="cmt-header-right">
            <van-icon name="like" size="16" color="red"
            v-if="obj.is_liking === true"
            @click="likeFn(true,obj)"
            />
            <van-icon name="like-o" size="16" color="gray"  v-else
               @click="likeFn(false,obj)"/>
          </div>
        </div>
        <!-- 主体区域 -->
        <div class="cmt-body">
      {{obj.content}}
        </div>
        <!-- 尾部区域 -->
        <div class="cmt-footer">{{fromDate(obj.pubdate)}}</div>
      </div>
    </div>
    </van-list>
    <!-- 发布评论区域 -->
    <div>
      <!-- 底部添加评论区域 - 1 -->
<div class="add-cmt-box van-hairline--top" v-if="isShow">
    <van-icon name="arrow-left" size="0.48rem" @click="$router.back()" />
    <div class="ipt-cmt-div" @click="changeShowFn">发表评论</div>
    <div class="icon-box">
        <van-badge  :content="totalCount || '' " max="99">
            <van-icon name="comment-o" size="0.53333334rem" @click="moveFn" />
        </van-badge>
        <van-icon name="star-o" size="0.53333334rem" />
        <van-icon name="share-o" size="0.53333334rem" />
    </div>
</div>

<!-- 底部添加评论区域 - 2 -->
<div class="cmt-box van-hairline--top" v-else>
    <textarea
    placeholder="友善评论、理性发言、阳光心灵"
     v-fofo
     @blur="blurFn"
     v-model="commentText "
     ></textarea>
    <van-button type="default"
    :disabled= "commentText.legth === 0 "
    @click="sendFn"
    >发布</van-button>
</div>

    </div>
  </div>
</template>

<script>
import { getCommentsListAPI, likeCommentsAPI, unLikeCommentsAPI, sendCommentAPI } from '@/api'
import dayjs from 'dayjs'
import 'dayjs/locale/zh-cn' // ES 2015
import * as relativeTime from 'dayjs/plugin/relativeTime'

dayjs.locale('zh-cn') // use locale
dayjs.extend(relativeTime)
export default {
  data () {
    return {
      commentList: [], // 评论数组
      isShow: true, // 底部评论是否出现
      totalCount: 0, // p评论的数量
      commentText: '', // 发布评论的内容
      loading: false, // 底部加载状态
      finished: false, // 底部是否加载完成
      lastId: null // 下一页评论数据的偏移量评论id
    }
  },
  props: {
    artId: [Number, String]
  },
  methods: {
    // 加载更多
    onLoad () {
      if (this.commentList.length > 0) { this.getCommentsListFn() }
    },
    fromDate (dataStr) {
      dayjs.extend(relativeTime)

      var a = dayjs()
      var b = dayjs(dataStr)
      const c = a.to(b) // in 2 years
      return c
    },
    // 点击评论喜欢
    async  likeFn (bool, obj) {
      if (bool === true) {
        // 取消点赞
        await unLikeCommentsAPI(obj.com_id)
        obj.is_liking = false
      } else {
        // 点赞
        await likeCommentsAPI(obj.com_id)
        obj.is_liking = true
      }
    },
    // 点击发表评论->输入框出现
    changeShowFn () {
      this.isShow = false
      this.$nextTick(() => {
        window.scrollTo(0, document.documentElement.scrollHeight - window.innerHeight)
      })
    },
    // 评论输入框 -> 失去焦点事件
    blurFn () {
      setTimeout(() => {
        this.isShow = true
      })
    },
    // 点击评论 ->滚到评论区
    moveFn () {
      // 公式:直接获取莫个标签,调用scrollIntoView() 它此标签自动滚入到页面最上边
      // 如果底部没有更多标签,尽可能的往上滚动(文章特别长,无评论也可以测试)
      document.querySelector(' .like-box').scrollIntoView({
        behavior: 'smooth'
      })
    },
    // 发布功能
    async sendFn () {
      // console.log(this.commentText)
      const res = await sendCommentAPI({
        target: this.artId,
        content: this.commentText
      })
      console.log(res)
      // this.getCommentsListFn()
      this.commentList.unshift(res.data.data.new_obj)
      document.querySelector(' .like-box').scrollIntoView({
        behavior: 'smooth'
      })
    },
    // 请求评论列表
    async getCommentsListFn () {
      const res = await getCommentsListAPI({
        artId: this.artId,
        offset: this.lastId
      })
      if (res.data.data.results.length === 0) {
        this.finished = true
      }
      this.commentList = [...this.commentList, ...res.data.data.results]
      this.totalCount = res.data.data.total_count
      this.lastId = res.data.data.last_id
      this.loading = false
    }

  },

  created () {
    this.getCommentsListFn()
  }

}
</script>

<style scoped lang="less">
.cmt-list {
  padding: 10px;
  .cmt-item {
    padding: 15px 0;
    + .cmt-item {
      border-top: 1px solid #f8f8f8;
    }
    .cmt-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      .cmt-header-left {
        display: flex;
        align-items: center;
        .avatar {
          width: 40px;
          height: 40px;
          background-color: #f8f8f8;
          border-radius: 50%;
          margin-right: 15px;
        }
        .uname {
          font-size: 12px;
        }
      }
    }
    .cmt-body {
      font-size: 14px;
      line-height: 28px;
      text-indent: 2em;
      margin-top: 6px;
      word-break: break-all;
    }
    .cmt-footer {
      font-size: 12px;
      color: gray;
      margin-top: 10px;
    }
  }
}
/*美化 - 文章详情 - 底部的评论页面 */
// 外层容器
.art-cmt-container-1 {
  padding-bottom: 46px;
}
.art-cmt-container-2 {
  padding-bottom: 80px;
}

// 发布评论的盒子 - 1
.add-cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  box-sizing: border-box;
  background-color: white;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 46px;
  line-height: 46px;
  padding-left: 10px;
  .ipt-cmt-div {
    flex: 1;
    border: 1px solid #efefef;
    border-radius: 15px;
    height: 30px;
    font-size: 12px;
    line-height: 30px;
    padding-left: 15px;
    margin-left: 10px;
    background-color: #f8f8f8;
  }
  .icon-box {
    width: 40%;
    display: flex;
    justify-content: space-evenly;
    line-height: 0;
  }
}

.child {
  width: 20px;
  height: 20px;
  background: #f2f3f5;
}

// 发布评论的盒子 - 2
.cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 80px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  padding-left: 10px;
  box-sizing: border-box;
  background-color: white;
  textarea {
    flex: 1;
    height: 66%;
    border: 1px solid #efefef;
    background-color: #f8f8f8;
    resize: none;
    border-radius: 6px;
    padding: 5px;
  }
  .van-button {
    height: 100%;
    border: none;
  }
}
</style>
